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The U-Boats that Surrendered. U-1407 (HMS Meteorite) in the Royal Navy - 1945 to 1949

by Derek Waller

Introduction

1. At the end of the war in Europe in May 1945, 156 U-Boats surrendered. Of these, 10 were allocated to each of the three Allies (UK, USA and USSR) later in the year, one was repaired and commissioned into the French Navy, four were repaired and commissioned into the Norwegian Navy, three were scrapped in the Norwegian ports in which they had surrendered, two were sunk by the US Navy in February 1946, and 116 were sunk by the Royal Navy in Operation Deadlight between November 1945 and February 1946.

2. The Potsdam Agreement signed on 2 August 1945 included the decision to allocate just 10 U-Boats to each of the three Allies for technical assessment and experimental purposes. This led to the creation of the Tripartite Naval Commission (TNC) which was charged with determining the list of U-Boats to be allocated to each country. Thus, they recommended which U-Boats should be retained by the UK, one of which was the Type XVIIB U-Boat, U-1407, which was powered by a Walter gas turbine using high-test peroxide (HTP) as its fuel. As a result, U-1407 was transferred from Germany to the UK in August 1945 and, after repair and renovation, was commissioned into the Royal Navy as HMS Meteorite.

3. The purpose of this paper is to set out the Royal Navy’s policy for the acquisition of a limited number of U-Boats for research purposes, including U-1407, to explain the circumstances which led to the acquisition of this Type XVIIB U-Boat, and to describe U-1407’s service in the Royal Navy from 1945 to 1949.

Royal Navy Policy

4. Other than the retention of 10 U-Boats by each of the Allies for technical assessment and experimental purposes, a primary objective of the British Government was the elimination of the Kriegsmarine’s U-Boat fleet. This was agreed at the Potsdam Conference, with the British position being set out by the Prime Minister, Winston Churchill, at the 3rd Plenary Meeting of Allied Leaders at Potsdam on 19 July 1945, the minutes of which record that:

He considered that the U-Boats should be destroyed or sunk. However, some of the most modern U-Boats had devices of interest to all three Powers, and these should be shared. He therefore suggested that, as part of a final settlement, most of the U-Boats should be sunk, and the small balance required for research should be shared. The number kept by the three Powers should be a token; more in order to spread technical knowledge than to keep large numbers in existence.

5. Nevertheless, despite the tri-national nature of the Potsdam Agreement, the British and the Americans were determined (behind the backs of the Russians) to facilitate the earliest possible acquisition and study of the latest types of high-speed German U-Boat, especially the newly-developed, HTP-powered "Walter-boat", the Type XVIIB.

6. By the time the war in Europe ended, the Royal Navy’s First Sea Lord, Admiral of the Fleet Sir Andrew Cunningham, and the other members of the UK and US Combined Chiefs of Staff (CCS) had become very suspicious of the Russians and their future intentions, and one of the principles adopted by the CCS was that, if possible, no advanced technology should be allowed to go to Russia. Indeed, the First Sea Lord took specific action to ensure that advanced U-Boat technology should remain firmly in British and American hands.

7. The British attitude towards the Russians was exemplified later in the year when, on 13 August 1945, the Admiralty’s Directive to Vice Admiral Geoffrey Miles and Rear Admiral William Parry, the British Representatives on the TNC, made it clear that the Russians were to be denied access to the Walterwerke in Kiel. This was the factory where Dr Helmut Walter was developing a whole series of new and advanced technologies related to the use of HTP-powered gas turbines for German military purposes. These included the use of such turbines in submarines in order to produce the power required to drive them at high submerged speeds, and both the British and American authorities were determined that such technology should not fall into Russian hands. Thus, the unequivocal Directive included the statements that:

In particular, the Russians are not in any circumstances to be allowed access to the research laboratory, establishments or equipment of the Walterwerke.

The disposal of the latest types of U-Boat, fitted with hydrogen peroxide propulsion units, presents a problem of special importance and some difficulty. The most valuable boats are U-1406 and U-1407, which are fitted with the unit type 18X, and are capable of being completed within a reasonably short time. In addition, there are four badly damaged boats fitted with a smaller unit, type 17, namely U-792, U-793, U-794 and U-795.

It is desired to exclude the Russians from acquiring any of these special types of U-Boat. The Russians are, however, almost certainly aware of the existence of one or both types, and have a right under the [Potsdam] Protocol to inspect the boats. The exercise of this right, if a request is made, should be permitted, but inspection should be confined to the boats themselves and restricted to the minimum. You should report immediately any enquiries made by the Russians concerning these types [of U-Boat], and pending further instructions your case should be:

to maintain that U-1406 and U-1407 are the only boats of this type available for disposal within [the] Protocol.

to insist in concert with your USA colleague, that U-1406 and U-1407 are to be allocated to the USA and UK respectively.

The refusal of any of the U-792 to U-795 class to the Russians may be a delicate matter, but has great importance, since the acquisition of one of these boats might lead the Russians to put forward a claim under … the Protocol to examine and take equipment in the Walterwerke establishments for the purpose of providing spares for the U-Boats to be delivered to them. Further consideration is being given to the question of the disposal of these special types of U-Boat and establishments in relation to the Russians. Meanwhile, you should, if possible, avoid discussing the subject with the Russians.

8. There can be no doubt that the Americans and the British were determined to ensure that, where possible, the latest German submarine technology should be denied to the Russians at the same time that it was being exploited by the Royal Navy and US Navy. Whether or not this eventually worked out in practice is a matter of debate, since the Russians themselves gained access to the plans and a full-scale model of the projected HTP-powered Type XXVI U-Boat which would have been a larger and longer-range version of the Type XVIIB. Perhaps this accounts for the Russians’ surprisingly easy acquiescence to the UK and US proposal that the only two available, albeit unserviceable, Type XVIIB U-Boats should be allocated to Britain and America, an intention which the two Western Allies had made clear well before the TNC had even been constituted.

The Royal Navy Requirement for a Type XVIIB U-Boat

9. The idea of the Royal Navy conducting trials on captured U-Boats had first been considered in 1944, culminating in a letter from Admiral George Creasy, who was Admiral (Submarines), to the Secretary of the Admiralty (1992/SM.04070 dated 15 October 1944) titled "Types of German U-Boats Required for Post War Experiments and Tests". This revealed that the Royal Navy already possessed a great deal of intelligence about the various U-Boat types operated by and being developed for the Kriegsmarine, and the letter stated that:

A close study of the characteristics of all German U-Boats construction will be of great value, and to this end it is proposed … that a certain number of each type shall be taken over by the Navy for this purpose.

From both an operational and experimental point of view the type XXI U-Boat is of the greatest importance, followed by the type XXIII.

10. This proposal, which was made well before the war had ended, before any U-Boats had surrendered, and before it had been decided that the Allies would retain only 10 U-Boats each, was modified by Admiral Creasy on 7 March 1945, when (in a Minute on Admiralty file A/S.W.1694/44) he added the HTP-powered U-Boats to the list, saying that:

Since that letter [of 15 October 1944] was written, fresh information has been received of newer types of U-Boat than the type XXI and XXIII … (Types XVII and XXVI). Admiral (Submarines) considers that numbers of these and any other new types will be required to at least the same scale [one in commission and one for spares] as for the type XXIII.

The Search for the Type XVIIB U-Boats

11. There were two separate, though linked, activities that needed to be undertaken in early May 1945 relating to the Type XVIIB U-Boats as far as the Royal Navy was concerned. The first was to capture the Walterwerke at Kiel before it could either be sabotaged by its German staff or captured by the Russians, and the second was to locate the U-Boats themselves and thus to ensure that they remained in British and American rather than Russian custody.

12. As far as the Walterwerke was concerned, the British and American intelligence staff knew well before the end of the war that gas turbine engines powered by HTP were being developed for use in U-Boats. Therefore, the capture of the factory and its staff in Kiel on 5 May 1945, even before any of the formal surrender arrangements had taken effect in the city, was the result of a carefully pre-planned and orchestrated joint UK/US intelligence-led process.

13. It was nevertheless both a dangerous and urgent action, especially because at the time the British and Americans were concerned that the Russians might not, as had been agreed, halt their westward advance on the east bank of the River Trave, but instead would attempt to advance to Lubeck, Kiel and the rest of Schleswig-Holstein, and perhaps even into southern Denmark. To counter this possibility, British forces had concentrated on reaching the Baltic coast at Wismar, arriving there on 2 May. Thus, at the time of the surrender in north-west Germany at 0001 hours on 5 May 1945, there was a large area of territory to the north of Lubeck and Hamburg, and to the south of the Danish border which was not occupied by British troops, and this included Kiel.

14. The result of the pre-planning meant that the British and American forces which had advanced into north-west Germany included amongst their formations a special unit (T-Force) charged with capturing and preserving equipment and facilities identified by Naval Intelligence as being required by the Royal Navy and the US Navy. However, when the surrender of German forces and facilities in the Kiel area came into effect, this unit was still behind the front line of the British Army, which was itself located at Lubeck, some 60 miles south of Kiel.

15. Elements of T-Force, including the Royal Naval 30 Assault Unit (30AU), therefore took steps to move to Kiel as a matter of urgency. T-Force had a list of some 150 targets in the Kiel area, of which the most important was the Walterwerke factory, and there was considerable concern that the Russians might attempt a seaborne operation to capture the city. On the other hand, there were dangers involved in moving through territory that had yet to be occupied by the British Army, and there were also some senior officers in both the Army and the Royal Navy who were anxious to exercise their rights to accept the formal surrender of Kiel personally.

16. Despite these hurdles, T-Force Kiel began its move north at 0800 hours on 5 May, and some three hours later had effectively (though somewhat informally) assumed control of Kiel and accepted the surrender of the German naval forces in the city. At the same time, a Royal Navy team from 30AU, led by Cdr Dunstan Curtis, RNVR, made haste to Tannenberg, just to the north of Kiel and near the eastern entrance of the Kiel Canal, where the Walterwerke factory was located, capturing not only the works but also Dr Helmut Walter and his senior staff. Despite this, there were a number of senior British officers who were not at all amused by T-Force’s apparently unilateral and independent action, and T-Force Kiel’s commander was subjected to considerable criticism despite his unit’s undoubted success.

17. However, in the end it all worked out well, the Walterwerke was captured, and a signal message from Supreme Headquarters Allied Expeditionary Force (SHEAF) to the Admiralty on 7 May confirmed that:

Walter Research Works in Kiel intact. Dr Walter and staff available for interrogation. Development machinery set up for submarine high underwater speed partially complete.

18. The message also added that Reed will notify Numma and Ignatius. [Captain A G Numma, USN, and Captain W R Ignatius, USN, were both members of the United States Naval Technical Mission in Europe (NavTecMisEu)].

19. There was nevertheless a great deal of concern about the security of the project, and this was emphasised in another signal message on 7 May from the Director of Naval Intelligence (DNI) at the Admiralty to the Allied Naval Commander Expeditionary Force (ANCXF) in Germany, which said that:

It is requested that the secrecy of Walter-boats Type XVII and XXVI, particularly of the turbine propulsion units, should be preserved and not disclosed except to authorised Anglo-American personnel. This should apply also to component parts, drawings, plans, etc.

20. This was followed by a further message from the DNI to ANCXF on 21 May, which particularly reflected American concerns, as follows:

Following received from ComNavEu: Following dispatch received from NavTecMisEu - German submarine units 1405 to 1407 inclusive have Walter propulsion plants of great technical value. Were to have become operational 5 May 1945 and may be at sea or sunk. Request special guarding and notification location if surrendered. ComNavEu please advise Admiralty. Comment: It is reported that these three boats left Kiel on or about 5 May but their subsequent movements were not known. They may have been sunk or scuttled in the Denmark area.

21. As a result, ANCXF passed a message to the Flag Officers Kiel, Denmark and Norway on 22 May, stating:

U-Boat numbers 1405, 1406 and 1407 at present unlocated are of great technical interest. Immediate notification and special arrangements for guarding are to be made should they surrender. They are reported to have left Kiel about 5 May. They may have been scuttled or sunk in the Denmark area.

22. In respect of the Type XVIIB U-Boats themselves, two of them (U-1406 and U-1407) had been in Rendsburg near the eastern end of the Kiel Canal in late April 1945. However, on 1 May they left Rendsburg and moved (via the Kiel Canal) to Cuxhaven, where they arrived on 3 May. This was followed by the surrender agreement which came into effect at 0001 hours on 5 May and required the German armed forces in north-west Germany, including all naval ships and the U-Boats at Cuxhaven, to lay down their arms and surrender unconditionally. Thus, whilst there were local discussions about the possibility of scuttling the several U-Boats that were moored in the harbour at Cuxhaven, their COs were forbidden to scuttle or otherwise sabotage them, being threatened with shooting in the event of disobedience. This order was given by the Kriegsmarine’s Captain Kurt Thoma, the German Navy Local Area Commander, at a first meeting, and it was repeated by Vice-Admiral Gustav Kleikamp, the German Navy Regional Commander, at a second meeting.

23. The surrender arrangements were duly completed during 5 May. Thereafter U-1406 and U-1407 ceased active duty and the crews of both U-Boats were interned in one of the fish processing halls (Fischhalle IX) at the Cuxhaven Fishery Port. On 6 May, the then unmanned U-1406 and U-1407 were towed to the New Fishery Haven (Neuer Fischereihafen) in Cuxhaven port, where all the surrendered U-boats were left in the custody of two motor escort vessels, which had been designated as guard ships. The latter were moored alongside U-1406 and U-1407 in order to ensure that no unauthorized personnel should go on board the U-Boats.

24. However, on the night of 6/7 May, Naval Engineer Lieutenant Gerhard Grumpelt, who was an experienced U-Boat engineer, and who had been appointed to the Cuxhaven Naval Base after his former appointment as an instructor in the Baltic Submarine Combat Training Group, decided to scuttle the two Type XVIIB U-Boats. He was not a member of the crew of either U-1406 or U-1407, but was temporarily accommodated in one of the guard ships. So, he went on board U-1406 and U-1407 and scuttled each of them by opening the main vents and other flooding valves, and leaving the conning tower hatches open, an action for which he was subsequently court martialled, found guilty, and sentenced to imprisonment.

25. Almost at the same time, the British and Americans began their search for the nine Type XVII and Type XVIIB U-boats that had been built for the Kriegsmarine. The total comprised four smaller experimental U-Boats which were never intended for operational use, U-792, U-793, U-794 and U-795, which were known as either Type Wa201/Wk202s or Type XVIIs, and five Type XVIIB U-Boats designed for operations, U-1405, U-1406, U 1407, U 1408 and U 1409. Of the latter, only the first three had been completed and undertaken some trials, but none was operational. Construction of the other two had been abandoned in the Blohm & Voss Shipyard in Hamburg before completion, U-1408 (90%) and U-1409 (80%), and they had both also been badly damaged in RAF bombing raids in early April 1945.

26. The two incomplete and damaged U-Boats, U-1408 and U-1409, had been located in the Blohm and Voss Shipyard in early May, and a prime objective for the UK and US intelligence teams was therefore to find U-1405, U-1406 and U-1407. However, their locations were unknown, and it was neither a quick nor easy exercise to find them. The initial search was made by Captain Gilbert Roberts, RN, who had been sent to Germany by the C-in-C Western Approaches, and who reported on 30 May 1945 that he had carried out a search for U-1405, U-1406 and U-1407 on 26 May, and that:

after a long and difficult interrogation of local inhabitants, and a two-hour search, they had been discovered in the Rendsburg area of the Kiel Canal, all scuttled.

27. Unfortunately, this information turned out to be false, and salvage operations produced only U-792 and U-793, plus a type VIIC U-Boat (U-428 or U-748). The two Type XVII U-Boats were nevertheless recovered and taken to Kiel for possible restoration, and the search for the other Type XVIIs and the Type XVIIBs continued. Conditions in and around the heavily damaged ports and shipyards of north-west Germany were chaotic in May and June 1945, and it was not easy to identify the location of just a few specific U-Boats. Thus, in mid-June, the Kriegsmarine’s Rear-Admiral Eberhard Godt who was the ex-Chief of Operations in the U-Boat High Command, was sent on a tour of investigation with the specific task of locating the three “missing” Type XVIIB U-Boats.

28. After his tour, Admiral Godt returned to the ex-Kriegsmarine Headquarters at Flensburg and on 24 June reported that, whilst he had been unable to trace U-1405, he had located U-1406 and U-1407 at Cuxhaven. The results of the Admiral’s investigations are recorded in an ANCXF report to the Admiralty (Reference X.F.No.666/A/1121) dated 12 July 1945, which included the information that:

[The] Type XVIIB was the newest and most interesting of the U-Boats in existence at the end of the war. It was known that only three had been completed and had done trials and that none was operational. These three were U-1405, U-1406 and U-1407 and their location has been the subject of continuous enquiry.

Early information gave them as scuttled in the Kiel Canal [but this was incorrect].

The actual finding of U-1406 and U-1407 was a direct result of sending Admiral Godt on a tour of investigation.

[Admiral Godt] reported … that he had reliable information that U-1406 and U-1407 were scuttled in the New Fishery Haven, Cuxhaven. He had no knowledge of U-1405.

U-1405, U-1406 and U-1407 were in company and carrying out trials during April. Towards the end of that month they were at Rendsburg together. U-1405 returned to Kiel to have [a] schnorkel fitted, and it is the opinion of the [COs] of U-1406 and U-1407 that U-1405 was scuttled either in Kiel or Eckernforde. U-1406 and U-1407 proceeded to Cuxhaven about 1 May and on 3 or 4 May the German Senior Naval Officer at that port sent for the Commanding Officers and made them promise not to scuttle or sabotage their ships.

On the night of 7 May … U-1406 and U-1407 [were] scuttled by opening main vents and certain flooding valves and leaving the conning tower hatch open. No scuttling charges were fitted and no damage was done except by flooding. The two COs admitted removing one or two parts of the Walter Unit before their departure on 4 May.

Arrangements have been made for U-1406 and U-1407 to be taken from Cuxhaven to Kiel in order to receive expert assessment and attention preparatory to their departure for United Kingdom.

Information has now been received that U-1405 is almost certainly scuttled in Geltinger Bight and steps are being taken to confirm this. If found the vessel will be salvaged and taken to Kiel.

29. As a result of receiving this information, two of the Royal Naval officers charged with the task of locating the Type XVIIB U-Boats, Captain Blake, RN, and Commander Sanders, RN, travelled from Flensburg to the New Fishery Haven in Cuxhaven, where they found that arrangements were already underway to start salvage operation on 29 June.

30. Indeed, such was the UK and US interest in these Type XVIIB U-Boats that U-1406 and U-1407 were raised with great haste and moved to the Howaldt-Werke Shipyard in Kiel at the beginning of July 1945, though not before a fire had started in U-1406 and it had needed to be re-immersed in Cuxhaven harbour. Also, it was subsequently discovered that U-1405 had been scuttled by its crew on 5 May 1945 in Eckernforde Bay, just to the north-west of Kiel.

31. At the same time as this action was taking place, officers of the US Naval Technical Mission in Europe (NavTecMisEu) and the US Naval Submarine Mission in Europe (SubMisEu) were also searching for all the Type XVII and Type XVIIB U-Boats, especially for an example of the Type XVIIB. They quickly became aware that U-1406 and U-1407 had been located, and in late-July advised the United States Commander Naval Forces Europe (ComNavEu), and through him, the Commander in Chief United States Fleet (Cominch) that, in their opinion, just one Type XVIIB U-Boat (U-1406) would be sufficient for US Navy research purposes.

32. On 4 and 5 August 1945, Captain L V Honsinger, USN, from NavTecMisEu and Commander F Beltz, USN, from SubMisEu jointly surveyed all nine of the Type XVII and Type XVIIB U-Boats that had been located, most of which had previously been scuttled and then salvaged, and all of which were damaged and non-operational. On 5 August, they made the following report:

33. By early August it was therefore clear, despite any possible Russian aspirations, that U-1406 had been earmarked for the US Navy and that U-1407 (the best example) had been earmarked for the Royal Navy, the latter decision owing its genesis to the fact that Kiel was located in the British zone of northern Germany, and that even though there was the closest possible co-operation and co-ordination between the Royal Naval and US Naval forces in the area, the UK had, by definition, the first choice in respect of all the German material that was captured when the war ended, a fact that was readily acknowledged by both NavTecMisEu and SubMisEu.

34. All that then remained to be done was to ensure that these two U-Boats were formally allocated accordingly, that decisions were taken about where and how they were to be made serviceable, especially as both been scuttled, and that steps were taken to ensure that the seven remaining Type XVII and Type XVIIB U-Boats were put beyond any prospect of acquisition by the Russians.

35. It was originally thought that both U-1406 and U-1407 might be repaired and returned to an operational condition in a German shipyard using the local facilities and the experienced labour, but it was quickly realised that this would not be possible. The initial British proposal was to make use of the Blohm and Voss Shipyard in Hamburg, where the two Type XVIIB U-Boats had been built, whilst the Americans were inclined to use the Deschimag Shipyard in Bremen.

36. This approach had been sanctioned at a meeting held in the Admiralty on 17 July 1945 to discuss Admiralty Policy concerning the Future of Submarine Design, when the Chairman, Admiral Sir Frederic Wake-Walker, the 3rd Sea Lord and Controller of the Navy, stated that:

U-1407 should be repaired and brought to UK, all possible work being done in Germany.

37. However, as the British Government was determined that all the German naval shipyards should never again be used for military purposes, the proposals were quickly dismissed for political reasons, and in August the Admiral directed that U-1407, as well as the trial Mk 18X Walter unit which had been found in the factory in Kiel, should be brought to the UK immediately. He also indicated that Vickers at Barrow were to be entrusted with the project, since they were the UK’s leading submarine building firm. This policy concerning German shipyards had also been formally agreed at Potsdam on 1 August 1945 with the acceptance of the Report of the Technical Sub-Committee on the Disposition of the German Navy which, in respect of the repair of vessels allocated to the three Allies, said that:

Repair must be achieved within the time limits above provided [which was 6 months in the case of unserviceable submarines] without any increase of skilled employment in the German shipyards and without permitting the reopening of any German shipbuilding or connected industries.

38. The two unserviceable Type XVIIB U-Boats were therefore removed from Kiel in their extant condition for whatever repairs and further use was deemed appropriate by the US Navy and the Royal Navy. U-1406 was transferred to the USA as deck cargo on the US transport ship SS Shoemaker in September, and U-1407 was towed to the UK at the end of August.

The Walterwerke and the Walter Turbines

39. Having taken so much trouble and expended so much effort to capture the Walterwerke, the Royal Navy and US Navy were determined to exploit the submarine-related technology and so, between 5 May and 25 November 1945, the factory remained open under the direction of Commander I C Aylen, RN and Captain A L Numma, USN. The main intention was to re-create working examples of the Mk 17B (2,500 hp) and Mk 18X (7,500 hp) versions of the Walter turbine before they were shipped to the United States and the United Kingdom respectively as war booty. Indeed, such was the interest in HTP turbine technology that the Royal Navy’s First Sea Lord visited the Walterwerke on 22 July 1945, when Dr Walter personally demonstrated a Mk 17B unit that had been assembled from spare parts, and a similar visit was made by the US Secretary of the Navy, James Forrestal.

40. The result was that the Mk 17B Walter unit which had been captured was shipped intact to the USA, whilst the components of the trial Mk 18X Walter unit were moved to the UK in accordance with Admiral Wake-Walker’s directions. Additionally, all of the factory’s drawings, documents, and details of patents, together with some 50,000 microfilms were also moved to the UK. By November 1945 the Walterwerke factory no longer had any war-making potential, and it was then handed-over to the Military Government in Germany for use as a machinery store, but not before a team of Vickers’ engineers had visited the Walterwerke in October to learn what they could about the Walter unit, and to begin working out the details of the task ahead of them.

41. The parts for the Mk 18X Walter unit were all shipped to the Vickers Shipyard at Barrow, and Vickers was given an Admiralty contract to complete and test the unit. However, the latter needed to be completed in secret, and this caused a certain amount of concern in both the Admiralty and locally in Barrow as to how to ensure that the activity was kept away from prying eyes.

42. Shortly after the full German surrender on 9 May 1945, the Royal Navy’s plans for trials with captured U-Boats were put into effect. These started with a meeting on 25 June 1945, chaired by Admiral Creasy, to discuss Trials to be carried out in, and with, U-Boats. The minutes of the meeting did not mention the Type XVIIB U-Boats, because at that stage no serviceable example had yet been located in Germany, whereas examples of the other types in which the Royal Navy was especially interested were all located in the UK. Thus, the meeting concentrated on the arrangements for testing examples of the new high-speed type XXI and XXIII (“Elektro”) U-Boats that were already in the Royal Navy’s possession at Lisahally in N.Ireland.

43. As experience was to show, the Royal Navy’s trials with the type XXI U-Boats were most unsatisfactory. The first one selected for trials suffered from a whole series of defects, which included problems with its starboard main and auxiliary electric motors, and the second one had a battery explosion. The latter incident injured eight members of the crew and caused considerable damage, all of which combined to cause Admiral Creasy, in his report to the Admiralty, No.1311/SM.3530 dated 7 September 1945, to say that:

It is therefore submitted for very early consideration that all trials with the type XXI U-Boats be cancelled.

44. However, in the same report, and before the formal TNC allocations had been made, the Admiral also clarified the Royal Navy’s longer term interest in the U-Boats, including the specific Type XVIIB U-Boat, U-1407, by saying that:

If the above proposals are approved, Admiral (Submarines) will only require five U-Boats for trials, viz:

45. In the meantime, and without awaiting agreement from the TNC, the Royal Navy had transferred U-1407 to the UK. After it had been raised in haste on 1 July, it was first towed via the Kiel Canal to the Howaldt-Werke Shipyard in Kiel. Then, at the end of August, it was towed to Sheerness by the ex-Kriegsmarine tug Fohn 2, and from there it was towed to the Vickers Shipyard in Barrow-in-Furness by a British ocean-going tug, arriving there in the first week of September 1945 amid considerable secrecy and with zero publicity.

46. The TNC’s Inspection Team visited Barrow and inspected U-1407 on 6 September during its tour of UK. The comments of its leader, Rear Admiral Ernest Archer, RN, in his “Report of Inspection of German Naval Units in UK” (MO. 9016 dated 25 September 1945), make interesting reading:

On Thursday 6 September we flew to Barrow to see two submarines there, one of them U-1407 [The other was U-3017]. We lunched with Vickers on completion. As regards U-1407 the visit there could not have been better stage managed even if it had been intended to put our visitors [the Russians] off. The boat had not yet been ventilated and stank after her time on the bottom; she had slime all over her interior and the temporary lighting system was earthing onto the hull, so anyone touching it got a shock.

In consequence the time spent inside this craft was surprisingly short. The general impression gained was that the Russians knew about the Walter unit, also that they felt cheated insomuch as they expected us to hide her away, instead of which there she was prominently displayed in our shop window, albeit with a pretty hefty shock for all those who braved her interior. [Captain] Orel [of the Russian Navy] gave us his opinion that as a boat she could be considered scrap, though she might be of some technical interest.

47. As far as the TNC inspection and allocation processes were concerned, the British held the trump card, which was that almost all of the U-Boats that had either surrendered or been scuttled in the final days of the war were located either in the UK or in the British controlled zone of northern Germany. Thus, when the TNC considered the future of the Type XVII and XVIIB U-Boats, only U-1406 and U-1407 had been declared as available for allocation, even though the UK and US authorities knew full well that it would take more than 6 months to return each of them to a serviceable state. Also, whilst quite rightly, U-1405 had been classified as being scuttled in shallow water, and was therefore outwith the TNC allocation process, the fact that U-792, U-793, U-794 and U-795 had been raised, even before the TNC was constituted, was concealed from the Russians. It was asserted instead that these four U-Boats had also been “scuttled in shallow water.

48. The implication of the designation “scuttled in shallow water” was very important, because the TNC had agreed that:

Ships and craft sunk in shallow water, not in obstruction of normal shipping, should be destroyed in such a manner that the possibility of salvage and partial or full use for naval purposes is precluded.

And because the TNC had also agreed that:

The Power in whose zone of occupation …the[se] ships and craft … are located shall be responsible for executing the stipulated destruction.

49. The Royal Navy was also very closely involved with the TNC inspection of the Kriegsmarine’s naval vessels in northern Germany, including U-Boats, and this meant that there was special concern in the latter part of August 1945 about how to deal with the problem of the Type XVII U-Boats in the light of the impending TNC inspection team’s visit to Kiel in early September.

50. On 12 August, the British Naval C-in-C Berlin asked the Admiralty for disposal instructions for U-792, U-793 and U-795. In response, on 17 August, the Admiralty advised that any parts from U-792, U-793, U-1408 and U-1409 should be sent to the UK. On 23 August, the British Naval C-in-C Berlin then promulgated the TNC’s inspection programme. However, there had still been no response concerning the disposal of the three Type XVII U-Boats. It should be noted that there was no such concern about U-794, because it was powered by a closed-cycle oxygen unit, and this did not therefore attract the same level of interest as the HTP-powered U-Boats. Also, there was no consideration of U-1405 which had been scuttled in Eckernforde Bay. The wreck was demolished to prevent either its future use or any Soviet claims.

51. In view of the lack of a response from the Admiralty, the Flag Officer Schleswig-Holstein (FOSH) sent an immediate, top secret, message to the British Naval C-in-C Berlin on 27 August, saying:

Spare parts will be out of Walter submarines 792, 793 and 795 by noon Thursday. No definitive instructions have yet been received regarding disposal of hulls and remaining machinery. Failing instructions to the contrary by noon Thursday 30th intend to sink hulls in Kiel harbour. In event of questions being asked by members of Tripartite Commission, intend replying that these submarines have been destroyed with other types in accordance with policy laid down.

52. Predictably this caused a flurry of urgent advice, and on 28 August an immediate, top secret, response was sent by the British Naval C-in-C Berlin to FOSH and the Admiralty saying:

Hulls are not (R) NOT to be sunk unless definitive orders to do so are received from Admiralty. Admiralty are requested to signal as a matter of urgency guidance on what Russians should be told about these hulls if they ask and also about disposal of U-1406 and U-1407 in view of 7 May message [about the need for secrecy].

53. The Admiralty then entered the fray and, on 29 August, sent an immediate, top secret, instruction to the British Naval C-in-C Berlin, FOSH, and Admiral Miles (the senior British member of the TNC), saying:

Hulls of U-792, 793 and 795 should not repeat NOT be sunk. If Russians ask questions about these vessels, they should be informed that they were scuttled and their machinery sabotaged. It should be pointed out that they are incapable of being completed within the stipulated time. Anything likely to emphasise the importance of these vessels should be avoided, but if the Russians wish to inspect them, para 12 of instructions to Commission should be followed.

Russians are aware that U-1406 is in US hands and U-1407 in UK. Latter will be inspected by their delegation in this country. Admiral Miles has been instructed to insist in conjunction with the US representative that these two should be allocated to US and UK respectively.

Request you inform Admiralty and Admiral Miles of any Russian enquiries about any of these vessels.

54. Therefore, of the nine Type XVII and XVIIB U-Boats, only U-1406 and U-1407 were, despite their unserviceable condition, candidates for TNC allocation, and these two had (in effect) the Stars and Stripes painted on the side of one and the Union Jack painted on the side of the other. As a result it seems that, for whatever reason, the Russian members of the TNC agreed to their allocation to the USA and UK without demure. Also, in the absence of any contrary information, and in view of the large number of U-Boats that had been scuttled around the German and Danish Baltic coasts, the British assertion about the status of the remaining Type XVII and XVIIB U-Boats seems to have been accepted by the Russians at face value. Either the secrecy that the Admiralty had requested on 7 May 1945 had been maintained, or the Russians already knew enough about the Walter turbines to satisfy their own needs.

55. The initial allocations of 10 U-Boats to each of the three Allies were formally agreed at the 13th meeting of the TNC on 10 October 1945 and, after a number of minor changes had been negotiated, the final UK list comprised:

56. This list therefore included the Type XVIIB U-Boat, U-1407, despite the fact that as a result of the TNC visit to the UK and, as recorded in the visit report, it had been judged to be a Category “C” vessel which meant, according to the general TNC rules, that it was one of the “Naval ships and craft which were inoperable or those ships or craft whose construction or repair could not be completed within six months”. The implication of this definition was that U-1407 should not therefore have been available for allocation, but instead should have been destroyed. Nevertheless, the Russian members of the TNC acquiesced to the British desire to be allowed to keep U-1407.

57. The TNC allocation process was not however quite the end of the matter because, just before the TNC signed-off its final report on 6 December, Ernest Bevin, the British Foreign Secretary, received a letter from Mr F T Gousev, the Russian Ambassador in London, on 4 December, complaining that the British representatives on the TNC had failed to provide any information:

about the latest German Type XVII U-Boats with turbine propulsion which, as had been found, were under the custody of the British authorities.

58. The Admiralty’s response to the Foreign Office dated 19 December then revealed the true extent of the previous deception:

The Russians have referred in the letter of 4 December to the Type XVII submarines, of which, as you know, there are only two in existence [U-1406 and U-1407], and the Americans and ourselves were particularly anxious to secure them for U-research and to keep one apiece without letting the Russians get to know too much about their design and machines. This we have succeeded in doing.

Although Admiral Miles did declare them to the Commission at their first meetings, he did so in a supplementary list of inoperable submarines, as their construction was not at that time complete.

The Russians, fortunately, did not pay any great attention to them either at Berlin or in the course of the inspections. In view of their unique machinery and value in Naval research, we should like to avoid saying anything at this stage which might provoke the Russians into a further discussion about them.

Post-TNC Actions

59. By the end of February 1946, of the 10 U-Boats that had been allocated to the UK by the TNC, one had been transferred (on long term loan) to Canada, two had been transferred (on long term loan) to France, and only seven remained in the Royal Navy. Of these seven, four were type VIICs, one was a type XXI and one was a type XXIII. All the planned trials with these three types of U-Boat had either been completed or cancelled by the end of 1945, and they were all moored at Lisahally awaiting decisions about their future use or disposal.

60. The only U-Boat in which the Royal Navy had any serious remaining long-term
interest was the Type XVIIB (U-1407) at Barrow, the first CO of which was appointed on 25 September 1945 when U-1407 was given the Royal Navy Pennant Number N.25. This interest had been confirmed in a file minute from Admiral (Submarines), reference SM.3517/994 dated 16 November 1945, which said:

All the technical requirements of Admiral (Submarines) for the U-Boats have been completed with the exception of U-1407.

Royal Navy Perceptions of the Walter Propulsion Process

61. Whilst it would soon to turn its attention to the prospect of using nuclear power in its submarines, the importance to the Royal Navy in 1945 and 1946 of the prospect of developing the Walter turbine, with its HTP (Ingolin) fuel, as the most effective means of achieving air-independent high-speed underwater propulsion, cannot be over-emphasised.

62. This is illustrated in a series of minutes written recorded on Admiralty File No SRE 3239/45, as follows:

a. Vice Admiral Sir John Kingcome, Engineer-in-Chief of the Fleet, 12 January 1946:

As the use of Ingolin provides the only known means of obtaining submerged speeds of 20 knots and over, it has already been decided that it is essential to proceed, at the earliest possible moment, with the development of this type of machinery.

b. Engineer-in Chief, 30 January 1946:

It is considered essential that this research should proceed, as the whole future submarine policy depends on the successful development of these engines; this is a matter of outstanding importance and urgency.

c. Dr A P Rowe, Admiralty Deputy Controller (R & D), 1 February 1946:

It is considered likely that the outcome of the German work on submarines will present the defences of the Commonwealth with a problem second only to that of the atomic bomb. We now know that a true submarine capable of high underwater speeds for useful periods is attainable.

I therefore consider that E-in-C’s proposals ….. are of great importance and I wish to support them strongly. Apart from the need for evolving the high-speed true submarine for offensive purposes, I suggest it is an urgent matter to build one or two of these weapons so that the formidable defence problems they present can be studied.

63. In the case of U-1407, the Royal Navy was therefore very attracted by the possibility of HTP being an air-independent propulsion option. Thus, after the U-Boat arrived secretly at the Vickers Yard in Barrow under tow and in a generally poor condition internally, after being allocated Pennant Number N.25 on 25 September 1945, and then after being formally commissioned as HMS Meteorite on 26 August 1947, it was eventually refitted with a new Mk 17B HTP turbine engine. However, this needed further repairs and development under the personal supervision of Professor Helmut Walter and a small team of German engineers who had been taken secretly to Barrow to continue the work they had started in Kiel.

64. Dr Walter himself had been briefly moved to London for interrogation in late-May 1945 before being allowed to return to Germany to continue with his work, but on 1 January 1946 he and seven other engineers from the Walterwerke were transferred to Barrow where they were given contracts to continue their work on behalf of the British Government. Eventually, later in 1946, the German party comprised 14 men, 13 wives and 24 children, thus emphasising the importance that the UK and the Royal Navy accorded to the research into HTP propulsion in submarines.

65. This action was not however without controversy. Indeed, it was a topic which had even been considered in principle by the UK Chiefs of Staff on 21 August 1945, and about which the First Sea Lord recorded in his diary that:

Another paper on the use of German scientists in this country. There is no question that by bringing them over here we prevent the Russians getting at them and also take advantage of their brains and knowledge. There are however grave security risks.

66. It was therefore not surprising when, on 19 December 1945, in a written reply to a question in the House of Commons, the President of the Board of Trade had to explain to Members of Parliament why German scientists and experts were being brought to work in the UK. He gave an assurance that in no case would a German be brought in to undertake work that could equally well be performed by a British subject. Also, there was considerable concern expressed in the local press in Barrow in January 1946 about the presence of the German engineers, and especially about the possibility that they were receiving better accommodation than that enjoyed (or suffered) by the local people. At that stage, and in view of their recent wartime experiences, the people of Barrow were generally not happy to know that Germans were working in the Vickers Shipyard.

67. The Admiralty’s initial intention was that U-1407 (N.25) was to be used purely experimentally and that, if the planned trials were successful, a decision would then be taken as to its future use as a possible high-speed anti-submarine target for training purposes. The refitting of the submarine was however a particularly lengthy business which involved a complete overhaul, its re-equipment with new components brought from Germany, and a number of other major changes to the original U-Boat. The latter included the fitting of a new escape system, a complete change of the ventilation system, the replacement of all electrical equipment, and the removal of the torpedo tubes.

Preliminary First of Class Trials

68. The Royal Navy’s sea trials of the much-modified HMS Meteorite (as U-1407/N.25 was now named) did not begin until 1948. The submarine left the dock at the Vickers Yard in Barrow at the end of January and, despite the lack of its Mk 17B HPT turbine at that stage, it was decided to carry out preliminary First of Class trials off the west coast of Scotland, using just the diesel and electric motors for power.

69. The main object of these trials was to familiarise the crew with the submarine’s general handling and, particularly, to observe and understand its reaction to the controls, with a view to future high speed trials. These later trials, which successfully tested both surface and submerged speeds, surface and submerged turning circles, and diving and change of depth performance, took place between 10 and 13 March 1948, after which HMS Meteorite returned to Barrow to have the HTP turbine fitted.

70. In the meantime, between July and September 1947, on-shore combustion trials had been taking place with the HTP turbine plant. However, these revealed flaws in a number of components, and the final set of on-shore trials was not completed until July 1948, after which the HTP turbine was fitted to HMS Meteorite. Further surface trials then began, but these were not completed until October 1948 due to repeated postponements because of rough weather.

71. The results of these surface trials were very promising. A speed of over 14 knots was obtained, and the Walter engine worked very well, despite rough handling. A Royal Navy report written after the October 1948 surface trials, but before the full operational trials in March and April 1949, stated that:

Considerable confidence in the operation, as well as control and ease of handling the plant, was gained. The only engineering troubles experienced were of a general nature, and were not directly connected with the turbine unit itself.

72. The same report reviewed the “operational possibilities” arising from the experience with HMS Meteorite, and the latter led to the encouraging statement that:

The operational possibilities of a very fast moving submarine are obviously enormous. HTP is very expensive, but it is the only proven method in existence capable of propelling a submarine at high speeds for long periods. Any future HTP submarine would have a more powerful diesel engine and [electric] motor, and so some of the disadvantages of operating [HMS] Meteorite would not arise.

73. There were however a number of specific disadvantages highlighted in the report, which included:

The expense of HTP, which costs at least £300 per ton and is in short supply.
The need for a fulltime escort vessel for accommodation.
The need for a storage ship for the HTP
The length of time taken to transit from harbour to any exercise area. On the surface, and in anything but the calmest of seas, the casing was almost continuously under water.
Meteorite’s “grave” lack of astern power. Hence, she is unable to stop quickly in an emergency should one arise.
None of the machinery was mounted on rubber, and the submarine was very noisy, thus facilitating detection by surface ships.

74. However, despite these disadvantages, the report concluded that:

It is realised that the disadvantage of expense of an HTP submarine is undoubtedly large. But while it remains the only proven method of very high speed propulsion, it is considered that the disadvantage is outweighed by the speed/time factor. This speed would probably be used mainly for escaping after an attack. With its help big changes of direction and depth could rapidly be made whilst at the same time, large distances are being covered, thus increasing by enormous proportions the difficulties of an escort vessel.

Operational Trials

75. HMS Meteorite’s main operational trials, both on the surface and submerged, took place between 17 March and 30 April 1949, and are described in the report from the CO to Captain (S/m), Third Submarine Flotilla, reference No. H.32915 dated 1 June 1949.

76. The time between 17 and 24 March was taken up with the HTP fuelling process in the Barrow area, after which HMS Meteorite was towed from Barrow to Rothesay Bay on the west coast of Scotland. Then, between 27 March and 1 April, it carried out general handling trials and submarine drills, the results of which were recorded as:

HMS Meteorite is an outstandingly difficult boat to handle on the surface.

She is outstandingly easy to handle dived.

She will not turn at all unless she has headway.

HMS Meteorite has extremely little stern power and will not steer at all going
astern.

The turning circle on the surface is comparatively large.

Handling HMS Meteorite dived is as easy as handling her on the surface is
difficult.

HMS Meteorite is undoubtedly slow at changing depth.

77. However, that said, the trials report concluded that all the machinery had been proved, and that the crew had gained experience and confidence in handling the boat dived. Thus, the initial phase of the trials was considered to have been successfully completed.

78. The next stage comprised a series of initial surface trials of the HTP turbine between 1 and 5 April in Loch Long, Argyll, south-west Scotland, before HMS Meteorite was towed south to Loch Ryan for the main HTP-powered trials, both surface and submerged. The latter began on 6 April, and the report says that:

During this, and at all later high-speed trials, HMS Meteorite handled perfectly.

79. After that, the submarine was moved to the Campbeltown area, but though the first test runs on 7 April at a depth of 60 feet were successful, strong vibrations became evident at maximum power and speed, and it was shortly followed by a fire in the turbine room. However, the fire was easily extinguished, and was attributed to excessive oil in the turbine room bilges rather than any mechanical failure of the machinery itself.

80. The submerged high-speed trials continued on 11 April and, once again, they were all completely successful, giving rise to the CO’s comment that:

It was also during these runs that the staggering manoeuvrability of HMS Meteorite at high speeds was discovered.

81. This led to two important conclusions:

It is considered that a small and fast submarine, even with the very high manoeuvrability of HMS Meteorite at 14 knots, would be a very hard target for an A/S ship to sink.

It would have been extremely interesting to have been able to observe the manoeuvrability of HMS Meteorite if she had been refitted with the two [HTP] turbines as designed, thereby giving her a designed speed of 25 knots.

82. After a short lay-up at Greenock, a final set of noise trials took place on 29 April, before HMS Meteorite was towed back to Barrow, reaching there on 30 April 1949. However, despite the changes to the submarine, as well as the optimism concerning its propulsion system and the successful high-speed trials, HMS Meteorite was not popular with the Royal Navy crews, who regarded it as a risky piece of machinery. Nevertheless, the trial results were sufficiently encouraging for the Admiralty to place an order for two larger British-built experimental HTP-powered submarines, HMS Explorer and HMS Excalibur, with the original intention - which was not pursued because of the advent of nuclear propulsion - of eventually ordering an operational fleet of up to 12 such submarines.

83. Finally, as recorded in the Admiralty’s “Special Military Branch Acquaint” (SMBA) Serial No.3512 dated 17 June 1949 (written just 17 days after the report on HMS Meteorite’s operational trials had been submitted), HMS Meteorite was taken out of service with the Royal Navy. The Acquaint saying that:

Approval has been given to the scrapping of HM Submarine Meteorite after the examination and removal of certain items of equipment.

84. Then, within just a further month, Admiralty “Acquaint” SMBA Serial No.3530 dated 16 July 1949 recorded that:

HMS Meteorite was paid-off [decommissioned] on 8 July 1949.

85. Thereafter, the submarine that was once U-1407 was handed over to the British Iron
and Steel Corporation (BISCO) for scrapping, and then moved just a short distance from the Vickers Shipyard at Barrow to the Thomas Ward Ltd Ship-Breaking Yard at Barrow on 7 September 1949, prior to being broken-up for scrap during the remainder of 1949.

Conclusion

86. Despite the determination of both the UK Government and the Royal Navy to see the total elimination of the remaining German U-Boats at the end of the war, there was great interest in viewing and learning from German U-Boat designs and technology, particularly where it was perceived to be an advance on British submarine technology. Thus, the UK fully supported the retention of 10 U-Boats by each of the three Allies for technical assessment and experimental purposes. To this end, the Royal Navy was particularly interested in the very latest high-speed U-Boat types, and was keen to acquire and study one of the experimental Type XVIIB HTP-powered U-Boats.

87. The acquisition of U-1407 was part of a very carefully orchestrated intelligence-led joint UK/US plan, not only to locate, raise and move the U-Boat to the UK, but also to preclude the Russians from the process, to mislead the TNC, and to ensure that the staff and facilities of the Walterwerke factory at Kiel were captured by the Western Allies and then reserved exclusively for their future support.

88. As a result, U-1407 was allocated to the UK by the TNC in October 1945, and it was the only U-Boat operated by the Royal Navy after January 1946. It was formally commissioned as HMS Meteorite in August 1947, but no sea-going trials took place until 1948 after the completion of a comprehensive two and a half year overhaul, refit and upgrade. Indeed, the full operational trials did not take place until March and April 1949 and, though these were generally successful, the submarine was decommissioned in July 1949 shortly after the trials report had been submitted.

89. Finally, the very last chapter of the story of U-1407 in the Royal Navy was formally recorded in the Admiralty’s "Acquaint" SMBA Serial No 3597 dated 15 December 1949, which said that: